A work vehicle includes various devices such as engine accessories and a fuel tank in a rear or lower region of a seat. The seat can change its position to inspect these devices. U.S. Pat. No. 5,284,115 discloses an example of the work vehicle including a seat attached to a seat base mounted on a fender deck provided between front wheels and rear wheels. The work vehicle includes brackets arranged forward of the seat, and a transverse shaft extending transversely through the brackets. The seat is vertically swingable via the transverse shaft. The vehicle further includes two springs arranged rearward of the seat base to support a rear part of the seat in a cushioning manner. The seat base is provided with a toolbox covered with the seat.
The seat disclosed in U.S. Pat. No. 5,284,115 maintains a seating position by the weight of the operator and swings upward by the action of the springs as the operator leaves the seat. The unoccupied seat freely swings upward and thus easily flips over. While such an arrangement is advantageous to access the toolbox, the seat disadvantageously easily turns over when an unexpected force, such as blowing wind, is applied to the seat during parking, for example. If the seat remains turned over, rain or any foreign matters might enter the toolbox.